1. Field of the Invention
The present disclosure relates to an indirect illumination device for a vehicle for accurately setting a position of a light guide plate, reducing an assembling tolerance, and reducing the number of parts using diffusion ink instead of a diffusion sheet, preventing uneven distribution of light by limiting the assembling position of the light guide plate disposed in the inside of the indirect illumination device.
2. Description of Related Art
Recently, as the automotive industry evolves, driving performance of the vehicle is gradually improved, and various convenience device and safety device are on an introducing trend in the inside and outside of the vehicle to provide the convenience and safety of operation.
Further, as the quality of life is gradually enriched with a higher penetration of the vehicle, the vehicle's design has established as one of important purchase factor when purchasing the vehicle. Accordingly, the design of automobile has led to a growing trend of higher quality to promote purchasing power of the vehicle while meeting the demand of consumers.
As one way for luxuriously decorating the interior of the automobile, the indirect illumination device is provided in an indicator cover, a tray cover, a cup holder, a garnish etc. disposed in the vehicle to improve discrimination at night and to emit soft lighting.
Among this, the garnish is attached to the crash pad type and/or the trim type, and the surface thereof is provided with a wood grain film or is painted, thereby to more luxuriously decorate design of the interior.
On the other hand, FIG. 1 shows a structure of the indirect illumination device disposed in above parts, on a top of a base 1, a diffusion sheet 2 is provided, a light guide plate 3 of the diffusion sheet 2 is provided, a light source 4 is provided in one side of the light guide plate 3 to irradiate light from the side surface of the light guide plate 3.
Further, the top of the light guide plate 3 is disposed with a cover 5 forming an appearance. That is, the light irradiated from the light source 4 may emit into the outside of the cover 5 while being evenly diffusing through the light guide plate 3 and the diffusion sheet 2.
However, the structure of the indirect illumination device disposed in flat portion is not greatly limited in the above-described related art, but when applying to the structure to be curved or twisted such as the garnish portion of the crash pad or the door trim shown in FIG. 6, the problem occurs on the quality of the illumination.
That is, when the shape of a cover is bent or twisted, the light guide plate provided in the inside thereof is also bent or twisted. However, the assembling position of the light guide plate may not be accurately set according to a curvature of the cover due to the nature of structure of the light guide plate, thereby to generate excessive tolerance due to the installation position and the assembling of the light guide plate, such that the uneven distribution of the light occurs in the curve portion.
Further, the light guide plate and the diffusion sheet are bent wherein the wrinkle and folding occur due to the difference in the curvature of the inside and outside thereof in the inside of the diffusion sheet. Therefore, the light distributed into the diffusion sheet is also unevenly distributed, thereby to generate phenomenon to be concentrated with the light source in some section.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.